Japanese Laid-open Patent Publication No. 2011-25363 discloses an electric/pneumatic driving tool having a battery-powered electric motor and a compression device which is driven by the electric motor. In this driving tool, when air in a compression chamber is compressed to the maximum, a valve member is opened and the compressed air in the compression chamber is supplied into a driving cylinder. A driving mechanism is then actuated by this compressed air to drive in a struck material to be driven.